Thursday, May 9, 2013

Basic Prepping - Water Purification


Purify: a: to clear from material defilement or imperfection

              b: to free from undesirable elements

It had been a busy/hectic/strenuous week. Four of us had traveled to Haiti to meet a new priest. He was to take over the 24 parishes we attempt to help support. This is done through monetary efforts to help pay teachers and provide some meals for the children at various village schools. It also includes an annual trip to a number of different villages to show our physical support, bring medical teams and to let these people know they have not been forgotten . . . that whole phrase . . . . “not been forgotten” . . . . is why we are on this visit. To show them, by our physical presence, by our physical embrace, by our sharing a meal and attending Mass together . . . . that we have not, and will not, forget them.

We chose to “become one” with the villagers we go to visit. They take great pride in providing food and shelter on our visits. And, while we bring our own drinking water (yes the Culligan Man really does exist in Haiti), they provide “washed” dishes, cups and glasses. It’s impossible to not be exposed to the local water sources and all the little critters that live within.

Which is exactly why three of the four of us, me included, are having a rather bad time of it sitting in the Miami airport waiting for our trip home. It’s not going to be a pleasant trip home. Finally, the good Lord must have found a soft spot for us and our situation . . . . our flight was canceled. After a night in a hotel spent mostly nursing fevers and bathroom visits requiring “both ends” to be taken care of, we were finally travel worthy the next day and returned home. A career in the military that included trips to Vietnam, Japan, the Philippines and various countries in Central America insured that I had experienced these “intestinal challenges” before – but they had been blissfully absent for a number of decades. It was a good reminder that while water is a life giving liquid; it can also cause real problems if it’s not treated properly.

So let’s talk about purifying your water. How are you going to be sure that the three quarts or more that you will need to drink every day will not have you doubled over vomiting or running into the wilderness with your trowel looking to attend to your bad case of diarrhea?

The critters hiding in your water consist of protozoans (small, single celled animals) and an assortment of bacteria and viruses. Any one of them can give you a very bad day.

When I use the word “purify” I mean that these creatures are either dead or removed from the water you drink. And there are four primary ways to make that happen – heat, filtration, chemical treatment or exposure to Ultra-Violet (UV) light. Each has advantages and disadvantages. Some work better when used in combination with other techniques. But all will get you where you need to be – with a supply of pure water.



One of the items in my “Boogie Bag”/camping gear is a coffee pot (insides taken out) that acts as a container for my MSR Whisperlite gas stove. It’s a nice combination. And, should we choose to purify water by simply boiling it for coffee or hot chocolate, it does the task just fine.

By applying heat to water and maintaining a water temperature over 165F, the pathogens contained in the water are killed off within 30 minutes. If you take the temperature over 185F, that time is reduced to about 3 minutes. If your water is at a rolling boil, you can be assured that all the nasty little critters are dead. Most material suggests a rolling boil for 3 minutes, but the critters are long since dead once the boil begins.

There are disadvantages to this approach however – fuel and time. Fuel can quickly become a consideration. On week long treks or paddles I usually budget 2 quarts plus one pint of “white gas”. This is usually more than enough but if we also used the fuel to boil water to purify it, much more fuel would need to be carried.

Of course, wood can also be used. Unless you are in a long-term shelter condition and your wood is also used for cooking and warmth. While you can share the heat to purify water, it is time consuming and can go through fuel in a hurry.

Still . . . . all that said . . . . heating water is a proven way to insure your drinking water is pure.


Micro-filters are small, lightweight, simple to use and effective. While there is any number of options, for the past 15 years or so I have used MSR’s MiniWorks ceramic filter.

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The MiniWorks consists of a Pump Assembly that allows you to pump up to 1-liter per minute of purified water. An Intake Hose drops into the water allowing the pump to take in water through the Pre-Filter. In some areas, especially in water that is algae-rich, I suggest wrapping multiple layers of a coffee filter around the Pre-Filter to help keep out material that will clog the Ceramic Filter. The Pre-Filter Float allows you to adjust the depth that the Pre-Filter draws from. Typically you do not want to try and filter surface water since this holds some of the highest concentrations of critters. The heart of the filter is a Ceramic Filter with pores that are only 0.2 um (um = micro-meter = one millionth of a meter or 1 thousandth of a millimeter) in diameter. To give you some idea of how small this is, a hair is typically 100 um. Protozoans and Bacteria are typically .2mm to 4mm is size. This filter will filter out virtually all of these harmful critters. Where it falls short is in killing viruses – they are small enough to pass through a filter like this.

That said, few streams in the US are infected with viruses – your greatest danger are the larger critters and this filter will clean that water at the rate of 1 liter per minute.

Water seals at the intake end and the out flow end insure the two water systems do not mix. One big benefit of these filters is that they will screw directly on to a standard Nalgene bottle.

Water Bottels (Medium)

This goes a long way to insure the “dirty water” and “clean water” never meet.

The thinner the Ceramic Filter becomes, the poorer its filtering capability. Snapped onto the protective cap of the water filter is a Filter Gage. If the Ceramic Filter can pass through the gage opening, it is too thin and must be replaced.

I have used this particular filter for 15 years and it is, in my opinion, simply the best filter on the market today.

Chemical Treatment

One of the favorite treatment combinations is to use a chlorine tablet along with a second tablet to take away the taste.


This treatment will, indeed, purity your water – even without the above filter. You must be aware of the water temperature and the quantity to dose the water appropriately. My own personal preference is to use the MiniWorks filter and then augment with a chemical to kill off any viruses that may be in the water. My preferred product is something called Polar Pure.


In the bottle are Iodine crystals. Water is added to the bottle and it is allowed to sit for 30 minutes. You then pour two cap-fulls of this tincture into one liter of water, shake well and wait 30 minutes. This too will kill all the critters, including viruses. But, again, I prefer to use this as an adjunct to the MiniWorks filter. One problem with Polar Pure is that recently the FDA has decided that they can’t sell this product anymore because Iodine Crystals can be used in the production of Meth. Heavy Sigh! This single bottle can purify around 2,000 liters of water – I still have a ways to go! Keep an eye out for this product, if it comes back on the market – buy a couple bottles, it’s one of the best chemicals available for the treatment of water.

Ultra Violet – UV – Light

UV light is a relative newcomer to the treatment of water for backpackers. It has long been used as the final treatment of water from most water treatment plants. But a product that is battery operated and carried in a pack – that’s a fairly new development.

The big kid on the block for this product is SteriPen. While they have multiple iterations of their product, their mainstay is the SteriPen adventurer.


Simply fill your Nalgene with clear (take the chunks out) water, dip the “pen” into the water, it will turn on automatically. Stir it around gently for about 90 seconds and it will turn itself out. You water is now pure. Again, I would use this product in conjunction with the MiniWorks filter, but the literature and reviews of the product assure me that that is overkill.

And finally, a simple and virtually free purification system . . . the clear plastic water bottle.


This process has become very popular is third world countries as an alternative to building large, expensive and hard to maintain water treatment plants. The process is simple. Fill the bottles with clean (again, take the chunks out) water and lay them on a roof, on tinfoil – somewhere that they are exposed to sunshine all day long. After 8 hours, you have a bottle full of purified water. Obviously you will need a rotation system so you have drinking water while your next batch is purifying, but the simplicity and very, very low cost makes this an attractive alternative for many poor countries.

There you have it . . . . through the use of heat, filtration, chemicals and UV light, you can provide yourself with all the pure drinking water your need to keep yourself healthy and well hydrated.

You have all the time in the world NOW to prepare . . . . if you do not have a good water filter or a supply of chemicals or a SteriPen in your kit . . . . get one!

Pure water is simply a must in a survival situation . . . .


  1. I hadn't seen/used those mini-filters, will have to look into them, thanks!

  2. Jim - I think you'll like the filters. I'm going to pick up a Steripen before this summer's trips - will do a review sometime this fall. From what I've researched though, they sound pretty darn good.

  3. Boiling is one of the most secure and best routines for treating water,as indicated by the Federal Emergency Management Agency.Boiled water will taste better in the event that you re-oxygenate it by spilling the water here and there and then here again between two clean compartments.An alternate approach to murder accursed critters in your water is to treat it with bleach.Utilize a consistent, unscented mixed bag that contains 5.25 to 6 percent sodium hypochlorite, and purchase a considerable measure of small bottles,in light of the fact that bleach's strength reduces after its opened.To treat water,include 16 drops (1/8 of a teaspoon) to a gallon of water,mix and let stand for 30 minutes.Ceramic filters give great insurance against microorganisms, and they don't require any vitality use simply gravity.You simply dump the water in the top, and it filters down,The microorganisms can't get past the top.
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